The process of “weed eating,” or string trimming, is a necessary step in lawn maintenance that provides clean, finished lines around obstacles and areas inaccessible to a traditional lawn mower. This tool manages grass height along fences, garden beds, and sidewalks, ensuring a uniform appearance. Resolving the debate over whether to trim before or after mowing maximizes efficiency and achieves the best aesthetic outcome for the turf.
Understanding the Impact of Timing
The sequence in which these two tasks are performed significantly affects the overall cleanliness and health of the lawn. Some homeowners choose to use the string trimmer first, believing it allows them to clear the difficult, overgrown areas out of the way immediately. This method focuses on managing the perimeter growth before addressing the main body of the yard.
However, trimming before mowing creates a notable problem related to debris management. The trimmer, by its nature, throws grass clippings and small plant matter in every direction, scattering them widely across the paved and grassy surfaces. This requires the subsequent mowing pass to also function as a cleanup operation.
If the mower is not equipped with an effective bagging system, or if the grass is particularly dense, scattered clippings can be left behind. These residual pieces of plant matter can clump together or settle into the lawn, creating an untidy appearance. The clippings can also smother the underlying turfgrass if they are heavy and wet, hindering light penetration and air circulation.
The Optimal Sequence: Trimming After Mowing
The superior approach is to always execute the string trimming operation after the main body of the lawn has been cut. This timing allows the mower to first establish the precise cutting height across the majority of the area. The trimmer can then be used to match this established height exactly around obstacles and edges, creating a visually uniform transition.
The primary logistical advantage of this sequence is the centralized collection of debris. When trimming is performed last, the clippings generated along the edges are deposited onto the freshly mowed lawn surface. The mower’s high-speed rotating blades create a powerful airflow capable of lifting and collecting this loose material.
This airflow acts as a vacuum, effectively pulling the scattered trimmer debris into the mower’s collection bag or recirculating it back into the mulching chamber. This one final pass of the mower over the trimmed areas drastically reduces the need for manual cleanup, resulting in a much cleaner finish on sidewalks and driveways.
Trimming after mowing also minimizes the risk of “scalping,” which is detrimental to turfgrass health. Scalping occurs when the grass blades are cut too short, potentially damaging the plant’s crown. If a person trims too aggressively before mowing, the subsequent pass with the lawn mower may compound that initial damage, severely stressing the grass around the perimeter.
When the mower sets the height first, the operator can adjust the trimmer to gently skim the grass to the same level, ensuring that no section is excessively defoliated. Maintaining a consistent height of cut promotes healthier root development and reduces the susceptibility of the grass to environmental stresses, such as heat or disease.
Advanced Techniques for Edging and Trimming
Focusing on the proper technique ensures the best possible result. It is helpful to distinguish between two specific actions: trimming and edging, which use the same tool but different orientations. Trimming involves holding the string horizontally to cut grass where the mower cannot reach, while edging requires holding the string vertically to create a sharp, clean line along paved surfaces like driveways and sidewalks.
When trimming, the operator should utilize only the very tip of the string line to slice the grass blades. Using the entire length of the string can cause the operator to inadvertently cut too deeply and damage the turf. Maintaining a consistent angle, typically around 10 to 15 degrees relative to the ground, facilitates a clean, even cut without tearing the grass.
A highly effective technique is to operate the string trimmer in a counter-clockwise direction relative to the operator. The rotational physics of the string head will then ensure that any resulting debris is thrown onto the lawn surface. This directional control assists the mower’s final cleanup pass by directing all the material toward the collection path rather than scattering it away from the cutting deck.
Always wearing appropriate personal protective equipment, including safety glasses or a face shield, is essential during any trimming operation. The high velocity of the nylon string can easily launch small pieces of stone, wood, or other hidden debris, which poses a safety risk to the operator and any nearby individuals.